Vanguard and the French nuclear submarine Triomphant collided somewhere in the Atlantic Ocean.

On February 6 the French Ministry of Defence reported that Triomphant "collided with an immersed object (probably a container)". The UK Ministry of Defence initially would not comment that the incident took place but it was confirmed on February 16 by First Sea Lord Sir Jonathon Band. He said that the collision occurred at low speed, and that there had been no injuries. Both vessels were damaged. Vanguard received damage to the outer casing in the area of the missile compartment on the starboard (right) side.